We propose to establish a Developing Center on Implementing Evidence-Based Practices for Children. To maximize the policy impact of the Developing Center (DC), it will be housed within the New York State Office of Mental Health (NYSOMH), with strong linkages to two established academic centers, The Mt. Sinai School of Medicine (MSSM) and Columbia University. The research agenda will advance service systems research by 1) targeting development of methods and strategies for improving the uptake of evidence-based practices (EBP's) in a state public mental health system and by 2) experimentally examining a set of theory-based strategies to improve EBP implementation efficiency and effectiveness. An overarching center principle is the promotion of collaborative research strategies with major stakeholders, including EBP treatment developers, families and family advocates, clinicians, clinic administrators, and policy-makers, including cabinet-level state authorities. The Operations Core will provide scientific and administrative oversight to the other Cores by strengthening linkages with family advocacy organizations, other state agencies, and other states engaged in child EBP implementation efforts (e.g., OH, CA, HI, and NM). The Principal Research Core will develop and pilot test strategies to enhance implementation of new clinical services by examining system, organizational, and service delivery variables among a network of outpatient clinics. The Research Methods Core will develop integrative methods and measures to improve understanding of implementation processes, drawing from established diffusion, organizational, and social-cognitive theories. The overall public health goal of the DC is to advance knowledge about effective implementation strategies for improving the uptake of EBP's in a state-funded public mental health system, thereby improving child and adolescent mental health.